Transient Gut Microbiota Modulation and Bacteroides Predict Constipation Recurrence in Cerebral Palsy: A 4-Year Synbiotics Study

Abstract Background: Children with cerebral palsy (CP) suffer high constipation rates (26-74%) linked to gut microbiota (GM) dysbiosis. While synbiotics show short-term efficacy, long-term GM stability post-intervention is unknown. Methods: In a 4-year longitudinal study, 25 CP children with chronic constipation received 6-month synbiotics. Fecal 16S rRNA sequencing was performed at baseline (Pre), 6 months (M6), and 48 months post-intervention (M48). Recurrence status defined subgroups (nonrecurrent CNC=21, recurrent CC=4). Results: Shannon diversity increased at M6 vs. Pre (Δ=1.2, P=0.019) but regressed to baseline at M48 (P=0.008). Baseline Bacteroides >0.1% predicted reduced recurrence risk (OR=3.2, 95%CI:1.5–6.8, P=0.009). Metagenomic prediction revealed persistent BCAA biosynthesis enrichment in CC vs. CNC at M48 (q<0.05), while CNC showed upregulated tryptophan metabolism. Conclusions: Synbiotic-induced GM benefits are transient in CP children. Baseline Bacteroides abundance and distinct microbial metabolic signatures may stratify recurrence risk, informing personalized long-term constipation management.